Attention, Dano - can't get the mail to work tonight???!!!

[TCups]

   
Dano:

See the link:

http://www.glenbrook.k12.il.us/gbssci/phys/Class/1DKin/U1L6c.html

Acceleration due to gravity is 32 ft/sec**2 or 9.8 m/sec**

distance = 18 ft = (0 f/s)*t + (1/2) * (32 ft/sec**2) * (t**2)

18 ft = (16 ft/sec**2) * (t**2)

(18/16) sec**2 = t**2

t = sq root of 1.125 = 1.0601 seconds of free fall in earth's gravity for 18 ft distance, with no wind resistance

v(terminal) = v(initial) + acceleration x time, so,

v - 0 + 32 ft/sec * 1.06 sec = 33.06 ft/sec after 106 sec.

And the kinetic energy in ft-pounds (actually ft-pounds/sec) for a 22 pound rig is:

33.06 ft/sec x 22 pounds = 727.3 ft-pounds/sec of energy